Human skeletal muscle cell differentiation is associated with changes in myogenic markers and enhanced insulin-mediated MAPK and PKB phosphorylation

Acta Physiol Scand. 2004 Apr;180(4):395-403. doi: 10.1111/j.1365-201X.2004.01259.x.

Abstract

Aim: We hypothesized that myogenic differentiation of HSMC would yield a more insulin responsive phenotype.

Methods: We assessed expression of several proteins involved in insulin action or myogenesis during differentiation of primary human skeletal muscle cultures (HSMC).

Results: Differentiation increased creatine kinase activity and expression of desmin and myocyte enhancer factor (MEF)2C. No change in expression was observed for big mitogen-activated protein kinase (BMK1/ERK5), MEF2A, insulin receptor (IR), hexokinase II, and IR substrates 1 and 2, while expression of glycogen synthase, extracellular signal-regulated kinase 1 and 2 (ERK1/2 MAP kinase) and the insulin responsive aminopeptidase increased after differentiation. In contrast to protein kinase B (PKB)a, expression of (PKB)b increased, with differentiation. Both basal and insulin-stimulated PI 3-kinase activity increased with differentiation. Insulin-mediated phosphorylation of PKB and ERK1/2 MAP kinase increased after differentiation.

Conclusion: Components of the insulin-signalling machinery are expressed in myoblast and myotube HSMC; however, insulin responsiveness to PKB and ERK MAP kinase phosphorylation increases with differentiation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / analysis
  • Blotting, Western / methods
  • Cell Differentiation / physiology*
  • Cells, Cultured
  • Creatine Kinase / metabolism
  • DNA-Binding Proteins / analysis
  • Desmin / analysis
  • Female
  • Hexokinase / analysis
  • Humans
  • Insulin / metabolism
  • MADS Domain Proteins
  • MEF2 Transcription Factors
  • Male
  • Middle Aged
  • Mitogen-Activated Protein Kinases / analysis*
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / physiology*
  • Myogenic Regulatory Factors / analysis
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation
  • Protein-Serine-Threonine Kinases*
  • Proto-Oncogene Proteins / analysis*
  • Proto-Oncogene Proteins c-akt
  • Receptor, Insulin / analysis
  • Transcription Factors / analysis

Substances

  • Biomarkers
  • DNA-Binding Proteins
  • Desmin
  • Insulin
  • MADS Domain Proteins
  • MEF2 Transcription Factors
  • MEF2A protein, human
  • MEF2C protein, human
  • Myogenic Regulatory Factors
  • Proto-Oncogene Proteins
  • Transcription Factors
  • Phosphatidylinositol 3-Kinases
  • Hexokinase
  • Receptor, Insulin
  • Protein-Serine-Threonine Kinases
  • Proto-Oncogene Proteins c-akt
  • Mitogen-Activated Protein Kinases
  • Creatine Kinase